Types of depression

Author: nicodemus
Published on: 2021-08-10 11:20:39   Updated On: August-10-2021 11:20:39

What is depression?

Depression is a common and serious mental disorder that affects the way you feel, the way you think and how you act. It is characterized by depressed mood, feelings of guilt, low self-worth, decreased appetite, disturbed sleep, poor concentration, low energy, loss of interest, loss of pleasure, among others. It is important to note that different people exhibit different symptoms of depression (Bhowmik et al., 2012).

Globally, depression has been identified as a major cause of disability and premature death. It is widespread across all age groups, prevalent in both genders, affecting individuals from all walks of life (Bembnowska & Josko-Ochojska, 2015). This article seeks to add to the existing body of literature on depression by highlighting the different types of depression, causes of the illness, its symptoms, and available interventions.

What causes depression?

According to research findings, there is no single cause of depression. However, it may occur as a result of three things, that is,

  • Depletion of monoamines,
  • Increased levels of cortisol, and
  • Inflammation

According to Bembnowska and Josko-Ochojska (2015), depression might be caused by a combination of various factors including:

Genetic factors

According to research findings, depression runs in families and hence, some people inherit genes from their parents which make them likely candidates for depression. If a person comes from a family with a history of depression, then, their genetic makeup makes them likely candidates to suffer from depression during their lifetime.

On the contrary, an individual may still have a genetic makeup that makes them vulnerable to depression but they fail to suffer from the illness in their entire lifetime.  

In addition, there are many cases where an individual may suffer from depression and yet they have no family history of depression.

Biological factors

These relate to changes in brain structure and or function. The functioning of the brain is a delicate process that employs use of chemicals known as neurotransmitters. These neurotransmitters aid in relaying messages between nerve cells in the brain.

Some neurotransmitters play a significant role in mood regulation. They include serotonin, dopamine, acetylcholine, nonrepinephrine, and gamma-aminobutyric acid. Therefore, when a person experiences a deficiency in any of these neurotransmitters, they are likely to suffer from depression.

Cognitive factors

These factors are concerned with how individuals perceive themselves and the world around them. In most cases, a person who is always pessimistic and negative is likely to suffer from depression in contrast to another person who is more optimistic and positive in matters life.

Environmental factors

These are events that take place in an individual’s surrounding that have a lot of bearing on their state of mind. When these events become too stressful to an individual, depression is a likely outcome. Life stressors such as financial difficulties, a serious family loss, a stressful job, relationship/marital conflict, are among environmental factors that may trigger a depressive episode in an individual.

Physical changes in an individual’s body

Research shows that physical changes that occur in the body of an individual are likely to be accompanied by mental changes. Medical conditions such as a heart attack, a stroke, cancer, hormonal disorders may trigger a depressive episode in an individual making them apathetic and unwilling to take good care of their body. 

What are the symptoms of depression?

Depression manifests differently for different people. Following is a description of symptoms of depression as manifested by different age groups.

Depression symptoms in adults

According to Bhowmik et al. (2012), the following symptoms of depression are associated with adults

  • Feeling sad or unhappy most of the time
  • Feeling guilty, worthless, or helpless most of the time
  • Irritability or frustration over flimsy reasons
  • Agitation and angry outbursts
  • Loss of interest/pleasure in activities one used to enjoy
  • Decline in sex drive
  • Insomnia or excessive sleeping
  • Decreased appetite that may lead to significant weight loss
  • Increased craving for food that may lead to significant weight gain
  • Increased restlessness
  • Slowed thinking, poor concentration, indecisiveness
  • Feeling tired, increased fatigue, decreased energy
  • Suicide ideation and or attempts
  • Crying spells for no valid reason
  • Experiencing aches, cramps, headaches, pains, and indigestion

Depression symptoms in children

Younger children may manifest the following symptoms of depression:

  • Sadness
  • Irritability
  • Hopelessness
  • Worry

Depression symptoms in adolescents and teens

Adolescents and teens may manifest the following symptoms of depression:

  • Anxiety
  • Anger
  • Avoiding social interaction

Depression symptoms in older adults

Older adults may manifest the following symptoms of depression:

  • Feeling dissatisfied with life in general
  • Feeling bored
  • Feeling helpless
  • Feeling worthless
  • Avoiding social interactions
  • Suicidal ideation or attempts

How is depression treated?

The first thing to do in the pursuit of treatment is to visit a mental health professional (psychiatrist/psychologist) or health care provider.

The specialist can examine you, conduct an interview, and perform laboratory tests, in an effort to rule out all the other conditions that may be causing similar symptoms to those of depression.

Once properly diagnosed, depression can be treated using medications, psychotherapy, or a combination of the two approaches.

Some valuable resources for treating depression:

What are the different types of depression?

According to Bhowmik et al. (2012), mental health practitioners recognize the following types of depression:

  1. Major depressive disorder (MDD)
  2. Dysthymia (persistent depressive disorder)
  3. Bipolar disorder (manic depression)
  4. Psychotic depression
  5. Seasonal affective disorder (SAD),
  6. Post-partum or postnatal depression (PPD)


  1. What is major depressive disorder?

Major depressive disorder (MDD) is a debilitating illness characterized by depressed mood, impaired cognitive function, diminished interests, reduced appetite, and disturbed sleep. It is also known as ‘clinical depression’, ‘major depression’, or ‘unipolar depression. The disease occurs twice as much in women than in men. Research findings indicate that one out of every six adults is at risk of suffering from MDD during their lifetime (Otte et al., 2016).

What causes major depressive disorder?

Major depressive disorder is associated with alterations that occur in regional brain volumes, specifically the hippocampus. The disease may also be triggered by functional changes that happen in brain circuits, such as the affective-salience network and the cognitive control network. In addition, disruptions in the main neurobiological stress-responsive systems (such as the immune system and the hypothalamic-pituitary-adrenal axis) can trigger MDD (Etkin et al., 2015).  

What are the symptoms of major depressive disorder?

According to DSM-5, a person suffering from major depressive disorder exhibits at least five of the following symptoms:

  • Depressed mood
  • Diminished interest in almost all activities
  • Loss of weight/weight gain
  • Loss of appetite/increased appetite
  • Insomnia or hypersomnia
  • Fatigue or loss of energy
  • Feelings of worthlessness, inappropriate guilt
  • Inability to think rationally, indecisiveness
  • Recurring thoughts of death, suicidal ideation/suicide attempts
  • Psychomotor agitation

How is major depressive disorder treated?

According to Otte et al. (2016), treatment of major depressive disorder involves use of:

  • Psychotherapy interventions, and
  • Pharmacological treatment

Psychotherapy approach utilizes the following interventions:

  • Cognitive-behavioural therapy – teaches MDD patient how to identify negative thought patterns and replace them with positive ones.
  • Behavioural activation therapy – focuses on increasing MDD patient’s positive activities with the aim of providing them with a sense of pleasure.
  • Psychodynamic therapy – assists MDD patient to comprehend how earlier life experiences, emotions and thought patterns have contributed to their present illness.
  • Problem-solving therapy – imparts MDD patients with creative problem-solving skills to help them identify and overcome potential barriers to goal achievement.
  • Interpersonal therapy – imparts people with skills for identifying and resolving problems that arise in relationships such as interpersonal conflicts, impoverished relationships, and role transitions.
  • Mindfulness-based therapy – here, MDD patients engage in frequent meditative practice during which they focus on experiences, feelings, and thoughts in a non-judgemental manner, learning to accept matters as they are without trying to adjust them.

Pharmacological treatment of MDD utilizes glutamatergic antidepressants for example ketamine. Patients who fail to respond to pharmacological treatment(s) are usually subjected to an advanced form of medication called electroconvulsive therapy (Otte et al., 2016).

  1. What is dysthymia?

Dysthymia is a chronic mood disorder that persists for no less than two years in adults, and at least a period of one year in adolescents and children.

What causes dysthymia?

Dysthymia, also known as persistent depressive disorder, is caused by anomalous neurotransmitter signaling and hormonal abnormalities. Factors that perpetuate these abnormalities include social isolation, chronic stress, and childhood or adult trauma (Griffiths et al., 2000).

What are the symptoms of dysthymia?

Moch (2011) identified the following symptoms of dysthymia:

  • Depressed mood
  • Fatigue
  • Low self-esteem
  • A sense of hopelessness
  • Insomnia (lack of sleep) or hypersomnia (excessive sleep),
  • Poor appetite or hyperphagia (that is, overeating),
  • Poor concentration
  • Difficulty in making decisions

How is dysthymia treated?

Dysthymia is treated using both pharmacotherapy and psychotherapy approaches. However, a combination of the two methods has proven to be more effective than when either of them is used in isolation (De Lima & Hotopf, 2003).

Pharmacotherapy approach involves use of:

  • Selective serotonin reuptake inhibitors (SSRIs)
  • Monoamine oxidase inhibitors (MAOIs), and
  • Tricyclic antidepressants (TCAs)

Among the three, SSRIs are most preferred because they are better tolerated compared to the rest (De Lima & Hotopf, 2003).

Hollon and Ponniah (2010) identified the following psychotherapy approaches used to manage dysthymia:

  • Cognitive therapy – involves training patients on how to correct negative thought patterns.
  • Behavioural therapy – avails strategies that help dysthymia patients overcome feelings of helplessness, deficiencies, and stress.
  • Psychodynamic therapy – analyses emotional conflicts vis-a-vis childhood experiences and seeks to enhance insight via retrospective introspection.
  • Interpersonal therapy – provides techniques for coping with disputes, losses, and separation.
  • Supportive therapy – entails providing advice, compassion, education, encouragement and reassurance to patients suffering from dysthymia.
  1. What is bipolar disorder?

Bipolar disorder is a brain illness that results in an unusual shift in mood, level of activity, energy, and ability to undertake daily tasks. It is characterized by “periodic” or “cyclic” illness, where patients cycle “up” into a manic episode(s), and thereafter, cycle “down” into a depressive episode, from which they eventually recover.  Bipolar disorder is also known as manic depressive illness (Yadav et al., 2013).

What causes bipolar disorder?

Yadav et al (2013) established that bipolar disorder is caused by three main factors, including:

  • Environmental factors
  • Genetic factors
  • neurochemical factors

What are the symptoms of bipolar disorder?

Bipolar disorder is comprised of two episodes with the following symptoms:

Symptoms of the manic episode include:

  • Increased levels of activity/energy/restlessness
  • Extreme irritability
  • Abnormally high euphoric mood
  • Poor concentration
  • Unrealistic beliefs
  • Talking very fast
  • Increased sexual drive
  • Poor judgment

Symptoms of the depressive episode include:

  • Persistent anxious, empty, or sad mood
  • Feelings of helplessness, hopelessness, worthlessness, pessimism, and guilt
  • Loss of interest/pleasure in activities that were previously interesting/pleasurable
  • Loss of energy, feeling tired frequently
  • Poor concentration, bouts of amnesia, ineffective decision making
  • Irritability and restlessness
  • Inability to fall asleep (insomnia) or sleeping too much (hypersomnia)
  • Lack of appetite, increased appetite
  • Harbouring thoughts of suicide, suicide attempts

According to Bhowmik et al. (2012), bipolar disorders are characterized by cycles of mood (mood-switches) which include no less than one episode of mania (elevated mood) accompanied with episodes of depression. These disorders are both chronic and recurrent. The mood switches may by dramatic and rapid, or gradual. While in the depressed cycle, an individual exhibits one or all the symptoms of a depressive disorder.

Yadav et al (2013) identified four types of bipolar disorders.

  • Bipolar-I disorder – where a person has manic episodes that last for at least one week and depressive episodes that last for at least two weeks.
  • Bipolar-II disorder – where a person only experiences manic episodes, exhibiting high levels of activity, energy, productivity, and excitement.
  • Cyclothymia (also known as rapid cyclic bipolar disorder) – in this case, a person experiences at least four episodes in any given year, in any combination of hypomania, mania, or depression.
  • Bipolar disorder not otherwise specified (BP-NOS) – refers to a condition where a person experiences bouts of elevated mood, but which do not fall in the previously mentioned categories of bipolar disorders.

How is bipolar disorder treated?

Bipolar disorders can be treated using mood stabilizing medications. Lithium is an example of a mood stabilizing medication that can be used to treat mania. Anticonvulsant medications such as valproate and carbamazepine can be used to treat stubborn bipolar episodes (Yadav et al., 2013).

Psychotherapy as well as talk therapy have also proven effective in the treatment of bipolar disorder (Yadav et al., 2013). Examples of psychotherapy treatments for bipolar disorders include:

  • Cognitive Behavioural Therapy (CBT) – helps train bipolar disorder patients how to shift their thought patterns, from negative to positive thoughts.
  • Family-focused Therapy – helps train families with a member suffering from bipolar disorder on how to cope with the illness.
  • Interpersonal and social rhythm Therapy – empowers people with bipolar disorder to improve their relationships with others and how to manage their daily tasks.
  • Psycho-education – is a sensitization strategy that seeks to enlighten the public about bipolar disorder illness and the available treatments.

Atypical antipsychotic medications such as clozapine, olanzapine, risperidone, and ziprasidone have proven effective in treating bipolar disorder patients who fail to respond to lithium or anticonvulsant medication (Lieberman et al., 2005).

Electroconvulsive Therapy (ECT) may be adopted when pharmacotherapy and psychotherapy interventions fail to yield expected results (Yadav et al., 2013).

  1. What is psychotic depression?

Psychotic depression is a subtype of major depressive disorder (MDD) characterized by delusions (having irrational thoughts and/or fears), hallucinations (hearing or seeing things that aren’t really there), disorganized thinking, incoherent speech or some other break with reality (https://www.mind.org.uk/media-a/4293/psychosis).

A psychotic individual is one who has lost touch with reality. Psychotic persons hear “voices” and have strange and illogical ideas. For instance, such a person may think that others can ‘hear’ their thoughts or are trying to hurt, control, or even kill them. In other situations, a psychotic person may think they are some famous person, for example, the President of the republic, and such stuff (https://www.mind.org.uk/media-a/4293/psychosis).

A psychotic person easily gets angry for no valid reason. Such persons keep to themselves, sleep a lot during the day and remain awake at night. They may totally neglect appearance by not taking a bath or changing clothes. They are also hard to talk or say nonsensical things when they speak (http://www.mindclinics.org/library/assets/Psychotic%20Depression-033510.pdf).

What causes psychotic depression?

Research is still in progress regarding the actual cause of psychotic depression. However, the illness may be triggered by either of the following factors:

  • Abuse or trauma – a person who has been exposed to a traumatic event or abuse is likely to experience psychosis.
  • Physical injury – injuries to the head, or lead/mercury poisoning may cause one to experience hallucinations or delusions.
  • Illness – sicknesses such as high fever, Parkinson’s disease or Alzheimer’s disease may cause someone to experience hallucinations or delusions.
  • Recreational drugs – using recreational such as cannabis and LSD may make one to experience hallucinations and delusions.
  • Prescribed drugs – using certain prescribed drugs may cause one to experience psychosis.
  • Hunger – when hungry, one may experience hallucinations due to reduced blood sugar level.
  • Lack of enough sleep – when a person is deprived of adequate sleep for prolonged periods of time, they may experience hallucinations.  
  • Bereavement – a person who has lost a loved one may ‘hear’ their voice from time to time.  

What are the sysmptoms of psychotic depression?

An individual suffering from psychotic depression will have the following symptoms:

  • Psychosis
  • Insomnia
  • Physical immobility
  • Hypochondria
  • Anxiety
  • Constipation
  • Agitation
  • Intellectual impairment

Source: http://www.mindclinics.org/library/assets/Psychotic%20Depression-033510.pdf

How is psychotic depression treated?

Psychotic depression may be treated using both psychotherapy and pharmacotherapy interventions. These are explained in the following subsection.

  • Talking therapies – involves use of cognitive behavioural therapy for psychosis.
  • Arts therapies – involves use of arts by the patient in order to express how they feel. This method is used when the patient finds it difficult to talk about their experience.
  • Family interventions – this approach focuses on assisting family members to talk about what helps, plan for crises and problem solve.
  • Antipsychotic medication – this approach involves use of antidepressant (mood stabilizers) drugs to manage symptoms of the disease.
  • Neuromodulation – this entails use of brain-stimulation techniques including electroconvulsive therapy (ECT), deep-brain stimulation (DBS), transcranial direct-current stimulation (tDCS), and transcranial magnetic stimulation (TMS).
  1. What is seasonal affective disorder?

Seasonal affective disorder is a type of major depression that keeps recurring during a specific period of time each year. It thus follows a seasonal pattern which mostly occurs during winter season of the year (hence the term “winter blues”). For the depression to be categorized as SAD, it must occur for a period of no less than two years (American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders (DSM-5), 2013).

What causes seasonal affective disorder?

A person with seasonal affective disorder has difficulty regulating a neurotransmitter known as serotonin. Serotonin’s main function is mood balancing. Research findings indicate that during winter, persons with SAD happen to have higher levels of SERT in their system. High levels of SERT usually decrease the action of serotonin, which result in a depressed mood (McMahon et al., 2014).   

Individuals with SAD also experience production of excess melatonin. Melatonin is a hormone that causes a person to feel sleepy when darkness falls. Given that winter days are darker, persons with SAD will have more melatonin produced in their systems. As a result they tend to feel sleepy and lethargic most of the time (http://www.nhs.uk/Conditions/Seasonal-affective-disorder/Pages/Symptoms.aspx.).

Another cause of SAD in individuals is lack of exposure to sunlight which occurs during winter. Lack of exposure to enough sunlight results in less vitamin D production in the body of the individual. Vitamin D is believed to play a vital role in serotonin activity. Thus, deficiency as well as insufficient vitamin D leads to a depressive mood in SAD individuals (Kerr et al., 2015; Kjaergaard et al., 2012).

What are the sysmptoms of seasonal affective disorder?

According to Zauderer and Ganzer (2015) symptoms of seasonal affective disorder during winter season revolve around sad mood and low energy. They include the following:

  • Feeling sad
  • Feeling irritable
  • Frequent crying
  • Feeling tired
  • Feeling lethargic
  • Finding it difficult to concentrate
  • Feeling sleepy most of the time
  • Withdrawal from social functions
  • Craving for carbohydrates and sugars
  • Weight gain due to overheating
  • Suicide ideation

How is seasonal affective disorder treated?

Seasonal affective disorder is treated using a combination of several methods including antidepressant medication, vitamin D, light therapy, and counseling (Melrose, 2015).

  • Antidepressant medications

Given that SAD is related to a dysfunction in brain serotonin activity, second generation antidepressants (SGAs) for instance, Selective Serotonin Reuptake Inhibitors (SSRIs) have emerged as favourable antidepressant medication treatments. An example of SGA SSRI used to treat SAD is fluoxetine, also known as Prozac (Cheung et al., 2012).

Another SGA SSRI that can be used to treat SAD is Bupropion also known as Wellbutrin (Modell et al., 2005).

  • Vitamin D

According to Gloth III et al. (1999), people with SAD are advised to take vitamin D doses as this helps prevent symptoms of depression from manifesting during winter days.

  • Light therapy

Light therapy, also known as phototherapy or Bright Light Therapy (BLT) involves use of bright artificial light to replace the diminished winter sunshine. Light emitting boxes to be used for this purpose can be bought from specialized stores. These boxes have the capacity to emit full spectrum light whose composition is similar to sunlight (Eagles, 2009).

A person with SAD can be relieved of their depression symptoms by simply sitting in front of the light box early in the morning, and this should be carried on from fall until spring time (Weil, 2015).

  • Counseling

Counseling approaches that can be used to aid and support people with SAD include Cognitive Behavioural Therapy (CBT), which can be provided in a group format. Also to be used are programs that assist people to improve their diet by reducing intake of starches and sugars; increasing frequency of exercise, effectively manage stress, spending their time outdoors, and avoid social withdrawal (http://www.nhs.uk/Conditions/Seasonal-affective-disorder/Pages/Symptoms.aspx). 

  1. What is post-partum depression?

Post-partum depression is a mood disorder that mostly affects first-time mothers. Research shows that the disorder affects about 10 to 15% of new mothers (Gaynes et al., 2005).

What are the causes of post-partum depression?

For new mothers, the period following childbirth is usually accompanied by intense physiologic and psychological changes. As such, many vulnerable women end up developing depressive episodes. According to Kumar and Robson (1984), the following are some of the factors that place new mothers at risk of developing post-partum depression:

  • History of postpartum major depression before or during pregnancy
  • Antenatal depressive symptoms
  • History of mental illness in the family
  • Marital conflict
  • Exposure to stressful situations in the previous 12 months
  • Child-care related stressors
  • Personality factors such as introversion
  • Poor relationship with one’s own mother
  • Bipolar disorder
  • Not breastfeeding
  • Previous miscarriage
  • Unplanned pregnancy
  • Current drug or substance abuse by mother
  • Malformed infant from birth
  • Lack of social, emotional, and financial support from the partner
  • Low socioeconomic status
  • Untreated maternal sickness

What are the symptoms of post-partum depression?

Kammerer et al. (2009) identified several symptoms of past-partum depression including:

  • Mood swings
  • Loss of appetite
  • Fear of doing harm to the baby
  • Showing a lot of concern or extreme worry for the baby
  • Insomnia or oversleeping, even when the baby is awake
  • Feelings of guilt and helplessness
  • Sadness and excessive crying
  • Loss of interest in previously enjoyable hobbies and activities
  • Finding it difficult to concentrate or remember anything

How is post-partum depression treated?

Post-partum depression can be treated using a variety of methods depending on the root cause of the problem. Both pharmacological and non-pharmacological methods can be used. However, non-pharmacological method or psychotherapy is preferred because there is no infant exposure to medication during breastfeeding (Dennis & Chung-Lee, 2006). 

Two commonly used psychotherapy methods for treating post-partum depression are:

  • Cognitive behavioural therapy (CBT)
  • Interpersonal therapy (IPT)

Pharmacotherapy approach involves use of recommended drugs to mitigate the effect of post-partum depression. In this regard, selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, nortriptyline, paroxetine, and sertraline are frequently used (Payne, 2007).

More resources for handling depression:


American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), American Psychiatric Association, Arlington, Va, USA, 2013.

Bembnowska, M. and Josko-Ochojska, J. (2015). What causes depression in adults? Pol J Public Health, 125(2), 116-120. Available at: https://www.researchgate.net/publication/282841619

Bhowmik, D., Kumar Sampath, K.P., Srivastava, S., Paswan, S. and Dutta, A.S. (2012). Depression – sysmptoms, causes, medications and therapies, Pharma Innovation, 1,(32). Available at: https://www.researchgate.net/publication/284651508

Cheung, A., Dewa, C., Michalak, E.E. (2012). Direct health care costs of treating seasonal affective disorder: a comparison of light therapy and fluoxetine. Depression Research and Treatment. Available at: https://www.hindawi.com/journals/drt/2012/628434/

De Lima, M.S. and Hotopf, M. (2003). Benefits and risks of pharmacotherapy for dysthymia: a systematic appraisal of the evidence. Drug Safety, 26(1), 55-64. Available at: https://www.researchgate.net/publication/10980018

Dennis, C.L. and Chung-Lee, L. (2006). Postpartum depression help-seeking barriers and maternal treatment preferences: a qualitative systemic review. Birth, 33(4), 323-331. Available at: https://pubmed.ncbi.nlm.nih.gov/17150072/

Eagles, J.M. (2009). Light therapy and seasonal affective disorder. Psychiatry, 8(4), 125-129. Available at: https://www.researchgate.net/publication/257604097

Etkin, A., Buchel, C. and Gross, J.J. (2015). The neural bases of emotion regulation. Nature Reviews Neuroscience, 16(11), 693-700. Available at: https://www.researchgate.net/publication/283286862

Gaynes, B.N., Gavin, N., Meltzer-Brody, S. (2005). Perinatal depression: prevalence, screening accuracy, and screening outcomes. Evidence Report/Technology assessment (Summ), 119, 1-8. Available at: https://pubmed.ncbi.nlm.nih.gov/15760246/

Gloth III, F.M., Alam, W. and Hollis, B. (1999). Vitamin D vs broad spectrum phototherapy in the treatment of seasonal affective disorder. Journal of Nutrition, Health, Aging, 3(1), 5-7. Available at: https://pubmed.ncbi.nlm.nih.gov/10888476/

Griffiths, J., Ravindran, A.V., Merali, Z., Anisman, H. (2000). Dysthymia: A review of pharmacological and behavioural factors. Molecular Psychiatry, 5(3), 242-261. Available at: https://www.nature.com/articles/4000697

Hollon, S.D. and Ponniah, K. (2010). A review of empirically supported psychological therapies for mood disorders in adults. Depression and Anxiety, 27(10), 891-932. Available at: https://pubmed.ncbi.nlm.nih.gov/20830696/




Kammerer, M., Marks, M.N., Pinard, C. (2009). Symptoms associated with the DSM IV diagnosis of depression in pregnancy and post-partum. Arch Womens Ment Health, 12(3), 135-141. Available at: https://pubmed.ncbi.nlm.nih.gov/19337702/

Kerr, D.C., Zava, D.T., Piper, W.T., Saturn, S.R., Frei, B. and Gombart, A.F. (2015). Associations between vitamin D levels and depressive symptoms in healthy young adult women. Psychiatry Research, 227(1), 46-51. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420707/

 Kjaergaard, M., Waterloo, K., Wang, C.E.A. (2012). Effect of vitamin D supplement on depression scores in people with low levels of serum 25-hydroxyvitamin D: nested case-control study and randomized clinical trial. British Journal of Psychiatry, 201(5), 360-368. Available at: https://pubmed.ncbi.nlm.nih.gov/22790678/

Kumar, R. and Robson, K.M. (1984). A prospective study of emotional disorders in childbearing women. Br Journal of Psychiatry, 144, 35-47. Available at: https://pubmed.ncbi.nlm.nih.gov/6692075/

Lieberman, J.A., Stroup, T.S., McEvoy, J.P., Swartz, M.S., Rosenheck, R.A. and Perkins, D.O. Effectiveness of antipsychotic drugs in patients with chronic schizophrenia. The New England Journal of Medicine, 353(12), 1209-1223. Available at: https://pubmed.ncbi.nlm.nih.gov/16172203/

McMahon, B., Andersen, S., Madsen, M. (2014). Patients with seasonal affective disorder show fluctuations in their cerebral serotonin transporter binding. European Neuropsychopharmacology, 24(2), 319. Available at: https://www.researchgate.net/publication/280271243_P1i037

Melrose, S. (2015). Seasonal affective disorder: an overview of assessment and treatment approaches. Depression Research and Treatment. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4673349/

Moch, S. (2011). Dysthymia: More than minor depression. South African Pharmaceutical Journal, 78(3), 38. Available at: https://www.researchgate.net/publication/275637507

Modell, J.G., Rosenthal, N.E., Harriett, A.E. (2006). Seasonal affective disorder and its prevention by anticipatory treatment with bupropion XL. Biological Psychiatry, 58(8), 658-667. Available at: https://pubmed.ncbi.nlm.nih.gov/16271314/

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Otte, C., Gold, S.M., Penninx, B.W., Pariante, C.M., Etkin, A., Fava, M., Mohr, D.C. and Schatzberg, A.F. (2016). Major Depressive Disorder. Nature Reviews Disease Primers 2(1). Available at: https://www.researchgate.net/publication/308172676

Payne, J.L. (2007). Antidepressant use in the post-partum period: practical consideration. Am J Psychiatry, 164(9), 1329-1332. Available at: https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2007.07030390

Weil, A. (2015). Light Therapy. [Fact Sheet], Andrew Weil MD, Tempe, Ariz, USA. Available at: http://www.drweil.com/drw/u/ART03222/Light-Therapy.html.

Yadav J., Sharma, S.K., Singh, L. and Singh, T. and Chauhan, D. (2013). Bipolar disorder in adults. International Research Journal of Pharmacy, 4(6). 34-38. Available at: https://www.researchgate.net/publication/269846461

Zauderer, C. and Ganzer, C.A. (2015). Seasonal affective disorder: an overview. Mental Health Practice, 18(9), 21-24.

About the Author

Nicodemus is an MBA (strategic management) graduate of Egerton University (Kenya). He also holds a BSc degree in botany, zoology and chemistry, from the University of Nairobi (Kenya). He is proficient in the following computer programming technologies - HTML5, CSS3, JavaScript, Bootstrap, PHP, MySQLi and Python. He is an experienced researcher and writer in the fields of business management, information technology, biological sciences, and social sciences. He enjoys developing computer programs and web applications that address diverse user needs.

*Available for article writing and web design/development projects*
(contact: +254 723 753820, email: [email protected])


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